To describe the natural history and identify predictors of cancer-specific survival in patients who experience disease recurrence after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC).
Of 2,494 UTUC patients treated with RNU without neoadjuvant chemotherapy, 597 patients experienced disease recurrence. 148 patients (25%) received adjuvant chemotherapy before disease recurrence. Multivariable Cox regression model addressed time to cancer-specific mortality after disease recurrence.
The median time from RNU to disease recurrence was 12 months (IQR 5–22). 491 of 597 (82%) patients died from UTUC and 8 patients (1.3%) died from other causes. The median time from disease recurrence to death of UTUC was 10 months. Actuarial cancer-specific survival estimate at 12 months after disease recurrence was 35%. On multivariable analysis that adjusted for the effects of standard clinico-pathologic characteristics, higher tumor stages (HR pT3 vs. pT0-T1: 1.66, p=0.001; HR pT4 vs. pT0-T1: 1.90, p=0.002), absence of lymph node dissection (HR 1.28, p=0.041), ureteral tumor location (HR 1.44, p<0.0005) and a shorter interval from surgery to disease recurrence (p<0.0005) were significantly associated with cancer-specific mortality. The adjusted 6, 12 and 24 months post-recurrence cancer-specific mortality was 73%, 60% and 57%, respectively.
Approximately 80% of patients who experience disease recurrence after RNU die within two years post-recurrence. Patients with non-organ-confined stage, absence of lymph node dissection, ureteral tumor location and/or shorter time to disease recurrence died of their tumor faster than their counterparts. These factors should be considered in patient counseling and risk-stratification for salvage treatment decision-making.
urothelial carcinoma; upper urinary tract; recurrence; survival; prognosis
Most anticancer drugs entering clinical trials fail to achieve approval from the US FDA. Drug development is hampered by the lack of preclinical models with therapeutic predictive value. Herein, we report the development and validation of a tumorgraft model of renal cell carcinoma (RCC) and its application to the evaluation of an experimental drug. Tumor samples from 94 patients were implanted in the kidney of mice without additives or disaggregation. Tumors from 35 patients formed tumorgrafts, and 16 stable lines were established. Samples from metastatic sites engrafted at high frequency, and stable engraftment of primary tumors in mice correlated with decreased patient survival suggesting that tumor growth in mice may reveal the acquisition by the tumor of an ability to thrive at distant sites and metastasize. Tumorgrafts retained the histology, gene expression, DNA copy number alterations, and over 90% of the protein-coding gene mutations of the corresponding tumors. As determined by the induction of hypercalcemia in tumorgraft-bearing mice, tumorgrafts were able to act on the host causing paraneoplastic syndromes. In studies simulating drug exposures in patients, RCC tumorgraft growth was inhibited by sunitinib and sirolimus (into which temsirolimus is converted in humans), but not by erlotinib, which was used as a control. Dovitinib, a drug in clinical development, showed greater activity than sunitinib and sirolimus. The routine incorporation of models recapitulating the molecular genetics and drug sensitivities of human tumors into preclinical programs has the potential to improve oncology drug development.
xenograft; tumor graft; orthotopic; PK; NOD/SCID; kidney cancer; clear-cell renal cell carcinoma
While alterations in xenobiotic metabolism are considered causal in the development of bladder cancer (BCa), the precise mechanisms involved are poorly understood. In this study, we used high-throughput mass spectrometry to measure over 2,000 compounds in 58 clinical specimens, identifying 35 metabolites which exhibited significant changes in BCa. This metabolic signature distinguished both normal and benign bladder from BCa. Exploratory analyses of this metabolomic signature in urine showed promise in distinguishing BCa from controls, and also non-muscle from muscle-invasive BCa. Subsequent enrichment-based bioprocess mapping revealed alterations in phase I/II metabolism and suggested a possible role for DNA methylation in perturbing xenobiotic metabolism in BCa. In particular, we validated tumor-associated hypermethylation in the CYP1A1 and CYP1B1 promoters of BCa tissues by bisulfite sequence analysis and methylation-specific PCR, and also by in vitro treatment of T-24 BCa cell line with the DNA demethylating agent 5-aza-2′-deoxycytidine. Further, we showed that expression of CYP1A1 and CYP1B1 was reduced significantly in an independent cohort of BCa specimens compared to matched benign adjacent tissues. In summary, our findings identified candidate diagnostic and prognostic markers and highlighted mechanisms associated with the silencing of xenobiotic metabolism. The metabolomic signature we describe offers potential as a urinary biomarker for early detection and staging of BCa, highlighting the utility of evaluating metabolomic profiles of cancer to gain insights into bioprocesses perturbed during tumor development and progression.
Mammalian target of rapamycin complex 1 (mTORC1) is implicated in cell growth control and is extensively regulated. We previously reported that in response to hypoxia, mTORC1 is inhibited by the protein regulated in development and DNA damage response 1 (REDD1). REDD1 is upregulated by HIF-1, and forced REDD1 expression is sufficient to inhibit mTORC1. REDD1-induced mTORC1 inhibition is dependent on a protein complex formed by the tuberous sclerosis complex (TSC)1 and 2 (TSC2) proteins. In clear-cell renal cell carcinoma (ccRCC), the von Hippel-Lindau (VHL) gene is frequently inactivated leading to constitutive activation of HIF-2 and/or HIF-1, which may be expected to upregulate REDD1 and inhibit mTORC1. However, mTORC1 is frequently activated in ccRCC and mTORC1 inhibitors are effective against this tumor type; a paradox herein examined. REDD1 was upregulated in VHL-deficient ccRCC by in silico microarray analyses, as well as by quantitative real-time PCR, Western blot, and immunohistochemistry. Vhl disruption in a mouse model was sufficient to induce Redd1. Using ccRCC-derived cell lines, we show that REDD1 upregulation in tumors is VHL-dependent, and that both HIF-1 and HIF-2 are, in a cell-type dependent manner, recruited to, and essential for, REDD1 induction. Interestingly, whereas mTORC1 is responsive to REDD1 in some tumors, strategies have evolved in others, such as mutations disrupting TSC1, to subvert mTORC1 inhibition by REDD1. Sequencing analyses of 77 ccRCCs for mutations in TSC1, TSC2 and REDD1, using PTEN as a reference, implicate the TSC1 gene, and possibly REDD1, as tumor suppressors in sporadic ccRCC. Understanding how ccRCCs become refractory to REDD1-induced mTORC1 inhibition should shed light into the development of ccRCC and may aid in patient selection for molecular targeted therapies.
REDD1; DDIT4; mTORC1; VHL; RCC; HIF; nucleolus
Stereotactic body radiation therapy for low- to intermediate-risk prostate cancer has potential cost savings and may improve access to radiation, increase convenience, and boost quality of life.
The purpose of this study is to compare the cost-effectiveness of two external beam radiation therapy techniques for treatment of low- to intermediate-risk prostate cancer: stereotactic body radiation therapy (SBRT) and intensity-modulated radiation therapy (IMRT).
Materials and Methods:
A Markov decision analysis model with probabilistic sensitivity analysis was designed with the various disease states of a 70-year-old patient with organ-confined prostate cancer to evaluate the cost-effectiveness of two external beam radiation treatment options.
The Monte Carlo simulation revealed that the mean cost and quality-adjusted life-years (QALYs) for SBRT and IMRT were $22,152 and 7.9 years and $35,431 and 7.9 years, respectively. The sensitivity analysis revealed that if the SBRT cohort experienced a decrease in quality of life of 4% or a decrease in efficacy of 6%, then SBRT would no longer dominate IMRT in cost-effectiveness. In fact, with these relaxed assumptions for SBRT, the incremental cost-effectiveness ratio of IMRT met the societal willingness to pay threshold of $50,000 per QALY.
Compared with IMRT, SBRT for low- to intermediate-risk prostate cancer has great potential cost savings for our health care system payers and may improve access to radiation, increase patient convenience, and boost quality of life for patients. Our model suggests that the incremental cost-effectiveness ratio of IMRT compared with SBRT is highly sensitive to quality-of-life outcomes, which should be adequately and comparably measured in current and future prostate SBRT studies.
To critically review and illustrate current methodologic and statistical considerations for bladder cancer biomarker discovery and evaluation.
Original, review, and methodological articles, and editorials were reviewed and summarized.
Biomarkers may be useful at multiple stages of bladder cancer management: early detection, diagnosis, staging, prognosis, and treatment; however, few novel biomarkers are currently used in clinical practice. The reasons for this disjunction are manifold and reflect the long and difficult pathway from candidate biomarker discovery to clinical assay, and the lack of coherent and comprehensive processes (pipelines) for biomarker development. Conceptually, the development of new biomarkers should be a process that is similar to therapeutic drug evaluation - a highly regulated process with carefully regulated phases from discovery to human applications. In a further effort to address the pervasive problem of inadequacies in the design, analysis, and reporting of biomarker prognostic studies, a set of reporting recommendations are discussed. For example, biomarkers should provide unique information that adds to known clinical and pathologic information. Conventional multivariable analyses are not sufficient to demonstrate improved prediction of outcomes. Predictive models, including or excluding any new putative biomarker, needs to show clinically significant improvement of performance in order to claim any real benefit. Towards this end, proper model building, avoidance of overfitting, and external validation are crucial. In addition, it is important to choose appropriate performance measures dependent on outcome and prediction type and to avoid use of cut-points. Biomarkers providing a continuous score provide potentially more useful information than cut-points since risk fits a continuum model. Combination of complementary and independent biomarkers is likely to better capture the biologic potential of a tumor than any single biomarker. Finally, methods that incorporate clinical consequences such as decision curve analysis are crucial to the evaluation of biomarkers.
Attention to sound design and statistical practice should be delivered as early as possible and will help maximize the promise of biomarkers for patient care. Studies should include a measure of predictive accuracy and clinical decision-analysis. External validation using data from an independent cohort provides the strongest evidence that a model is valid. There is a need for adequately assessed clinical biomarkers in bladder cancer.
biomarker; diagnosis; prognosis; treatment; nomogram; decision-analysis; bladder cancer; statistics; statistical analysis
Bladder cancer remains a lethal malignancy that can be cured if detected early. DNA hypermethylation is a common epigenetic abnormality in cancer that may serve as a marker of disease activity.
We selected 10 novel candidate genes from the most frequently hypermethylated genes detected by DNA microarray and bisulfite pyrosequencing of bladder cancers and applied them to detect bladder cancer in urine sediments. We analyzed DNA methylation in the candidate genes by quantitative methylation specific real time PCR (qMSP) to detect bladder cancer in urine sediments from 128 bladder cancer patients and 110 age-matched control subjects.
Based on a multi-gene predictive model, we discovered 6 methylation markers (MYO3A, CA10, SOX11, NKX6-2, PENK and DBC1) as most promising for detecting bladder cancer. A panel of 4 genes (MYO3A, CA10, NKX6-2 and DBC1 or SOX11) had 81 % sensitivity and 97 % specificity, while a panel of 5 genes (MYO3A, CA10, NKX6-2, DBC1 and SOX11 or PENK) had 85 % sensitivity and 95 % specificity for detection of bladder cancer (AUC=0.939). Analyzing the data by cancer invasiveness, detection rate was 47 out of 58 (81 %) in non-muscle invasive tumors (pTa, Tis and pT1) and 62 out of 70 (90 %) in muscle invasive tumors (T2, T3 and T4).
This biomarker panel analyzed by qMSP may help the early detection of bladder tumors in urine sediments with high accuracy.
The panel of biomarker deserves validation in a large well-controlled prospectively collected sample set.
SWL and URS are highly effective treatments for urinary lithiasis. While stone size and location are primary determinants of therapy, little is known about other factors associated with treatment. Our objective was to identify patient, provider and practice setting characteristics associated with selection of ureteroscopy or SWL.
We used the Medicare 5% sample to identify beneficiaries with an incident stone encounter from 1997 –2007. Within this group, we identified beneficiaries undergoing SWL or URS for the management of urinary calculi. Multivariable regression models identified factors associated with use of URS.
The cohort comprised 9358 beneficiaries who underwent an initial procedure. SWL was used in 5208 (56%) beneficiaries, while URS was used in 4150 (44%). Females were less likely than males to undergo URS (OR 0.844, p = 0.006). Providers who more recently completed residency training employed URS more often (p = 0.023). Provider and facility volume were associated with initial procedure selection. The odds of a second procedure following initial SWL were 1.54 times that of URS (p<0.001).
Non-clinical factors are associated with use of URS or SWL for initial stone management, which may reflect provider and/or patient preferences or experience. Further investigation is required to understand the impact of these outcomes on quality and cost of care.
ureteroscopy; shock wave lithotripsy; outcomes
To evaluate the tolerability of escalating doses of stereotactic body radiation therapy in the treatment of localized prostate cancer.
Patients and Methods
Eligible patients included those with Gleason score 2 to 6 with prostate-specific antigen (PSA) ≤ 20, Gleason score 7 with PSA ≤ 15, ≤ T2b, prostate size ≤ 60 cm3, and American Urological Association (AUA) score ≤ 15. Pretreatment preparation required an enema and placement of a rectal balloon. Dose-limiting toxicity (DLT) was defined as grade 3 or worse GI/genitourinary (GU) toxicity by Common Terminology Criteria of Adverse Events (version 3). Patients completed quality-of-life questionnaires at defined intervals.
Groups of 15 patients received 45 Gy, 47.5 Gy, and 50 Gy in five fractions (45 total patients). The median follow-up is 30 months (range, 3 to 36 months), 18 months (range, 0 to 30 months), and 12 months (range, 3 to 18 months) for the 45 Gy, 47.5 Gy, and 50 Gy groups, respectively. For all patients, GI grade ≥ 2 and grade ≥ 3 toxicity occurred in 18% and 2%, respectively, and GU grade ≥ 2 and grade ≥ 3 toxicity occurred in 31% and 4%, respectively. Mean AUA scores increased significantly from baseline in the 47.5-Gy dose level (P = .002) as compared with the other dose levels, where mean values returned to baseline. Rectal quality-of-life scores (Expanded Prostate Cancer Index Composite) fell from baseline up to 12 months but trended back at 18 months. In all patients, PSA control is 100% by the nadir + 2 ng/mL failure definition.
Dose escalation to 50 Gy has been completed without DLT. A multicenter phase II trial is underway treating patients to 50 Gy in five fractions to further evaluate this experimental therapy.
To determine whether high risk patients with hematuria receive evaluation according to guideline recommendations.
Materials and Methods
We recently performed a screening study for bladder cancer using a urine-based tumor marker in 1502 subjects at high risk based on age over 50, ≥10-year smoking history, and/or a 15 year or more environmental exposure. We evaluated use of urinalysis (UA) within 3 years preceding the screening study. Chart review was performed to determine if this subset with microhematuria received any additional evaluation.
Of 1502 study participants, routine urinalysis was performed in 73.2% and 164 (14.9%) subjects had documented hematuria (>3 RBCs/HPF) prior to inclusion. Of these, 42.1% had no further evaluation. Additional testing included repeat urinalysis (36%), urine culture (15.2%), cytology (10.4%), imaging (22.6% overall: 15.9% CT, 4.3% IVP; 2.4% MRI) and cystoscopy (12.8%).
Three subjects with microscopic hematuria (2%) were subsequently found to have bladder cancer during the screening study but were not referred for evaluation based on their hematuria. The source of hematuria was unknown in 65%, infection in 22%, benign prostatic enlargement in 10% and renal stone disease in 4% but these results are based on incomplete evaluation since only 12.8% underwent cystoscopy.
Subjects at high risk for bladder cancer based on ≥10 years of smoking or environmental exposure with microscopic hematuria are rarely evaluated thoroughly and only 12.8% were referred for urologic evaluation. Further studies are needed to evaluate both the utilization and effectiveness of guidelines for hematuria.
Hematuria; Guidelines Recommendations; bladder cancer
To assess the association of lymphovascular invasion (LVI) with cancer recurrence and survival in a large international series of patients treated with radical nephroureterectomy (RNU) for upper urinary tract urothelial carcinoma (UTUC).
Patients and Methods
Data were collected on 1,453 patients treated with RNU at 13 academic centers and combined into a relational database. Pathologic slides were rereviewed by genitourinary pathologists according to strict criteria. LVI was defined as presence of tumor cells within an endothelium-lined space.
LVI was observed in 349 patients (24%). Proportion of LVI increased with advancing tumor stage, high tumor grade, presence of tumor necrosis, sessile tumor architecture, and presence of lymph node metastasis (all P < .001). LVI was an independent predictor of disease recurrence and survival (P < .001 for both). Addition of LVI to the base model (comprising pathologic stage, grade, and lymph node status) marginally improved its predictive accuracy for both disease recurrence and survival (1.1%, P = .03; and 1.7%, P < .001, respectively). In patients with negative lymph nodes and those in whom a lymphadenectomy was not performed (n = 1,313), addition of LVI to the base model improved the predictive accuracy of the base model for both disease recurrence and survival by 3% (P < .001 for both). In contrast, LVI was not associated with disease recurrence or survival in node-positive patients (n = 140).
LVI was an independent predictor of clinical outcomes in nonmetastatic patients who underwent RNU for UTUC. Assessment of LVI may help identify patients who could benefit from multimodal therapy after RNU. After confirmation, LVI should be included in staging of UTUC.
As the terminal differentiation products of human urothelium, uroplakins (UPs) would be expected to diminish during urothelial tumorigenesis. Surprisingly, recent studies found UPs to be retained even by well-advanced urothelial carcinomas, suggesting that the loss of UPs does not strictly parallel urothelial transformation. Little is known, however, about whether the status of UPs is associated with a particular pathological parameter, tumor’s biological behavior or patient outcome. Here we assessed UP expression by immunohistochemistry on tissue arrays from 285 patients with bladder urothelial carcinomas or non-tumor conditions. UPs were expressed in all 9 normal urothelial specimens, 63/74 (85%) patients with non-muscle-invasive urothelial carcinomas on transurethral resection, 104/202 (51.5%) patients who underwent radical cystectomy for advanced urothelial carcinomas, and 33/50 (66%) lymph node metastases. Normally associated with urothelial apical surface, UPs were localized aberrantly in tumors, including micro-luminal, basal-laminal, cytoplasmic or uniform patterns. In non-muscle-invasive diseases, there was no association between UP expression and disease recurrence, progression or mortality. In contrast, in invasive diseases, absent UP expression was significantly associated with advanced pathologic stage, lymph node metastases, disease recurrence and bladder cancer-specific mortality (p=0.042, p=0.035, p=0.023 and p=0.022, respectively) in univariate analyses. Furthermore, UP status was independent of key cell-cycle regulators, including p53, pRb, p27 and cyclin D1, thus excluding a functional link between these two groups of proteins. Our data demonstrate for the first time that persistent UP expression is associated with a favorable clinical outcome and that UPs may be used as adjunct markers for predicting the prognoses of patients with invasive and metastatic bladder carcinomas. Our results also suggest that UP-positive and –negative carcinomas have different clonal origins or may be derived from different cancer stem cells.
bladder cancer; uroplakin; progression; prognosis; transitional cell carcinoma
Chromosome missegregation and the resulting aneuploidy is a common change in neoplasia. The Aurora kinase A (AURKA) gene, which encodes a key regulator of mitosis, is frequently amplified and/or overexpressed in cancer cells, and the level of AURKA amplification is associated with the level of aneuploidy. We examined whether AURKA gene amplification is a biomarker for the detection of bladder cancer.
The effect of ectopic expression of Aurora kinase A (AURKA) using an adenoviral vector in simian virus 40–immortalized urothelial cells (SV-HUC) on centrosome multiplication and chromosome copy number was measured in vitro by immunofluorescence and fluorescence in situ hybridization (FISH), respectively. The FISH test was also used to examine AURKA gene copy number in exfoliated cells in voided urine samples from 23 patients with bladder cancer and 7 healthy control subjects (training set), generating a model for bladder cancer detection that was subsequently validated in an independent set of voided urine samples from 100 bladder cancer patients and 148 control subjects (92 healthy individuals and 56 patients with benign urologic disorders). An AURKA gene score (the proportion of cells with three or more AURKA signals) was used to produce receiver operating characteristic (ROC) curves and to calculate the specificity and sensitivity of the AURKA FISH test. Differences between mean AURKA scores in different pathogenetic groups of bladder cancer stratified according to histological grade and stage were tested by unpaired Mann–Whitney t tests or one-way Wilcoxon tests. All statistical tests were two-sided.
Forced overexpression of AURKA in urothelial cells induced amplification of centrosomes, chromosome missegregation, and aneuploidy, and natural overexpression was detectable in in situ lesions from patients with bladder cancer. The FISH test for the AURKA gene copy number performed on the validation set yielded a specificity of 96.6% (95% confidence interval [CI] = 92.3% to 98.5%) and sensitivity of 87% (95% CI = 79.0% to 92.2%) and an area under the ROC curve of 0.939 (95% CI = 0.906 to 0.971; P < .001).
Overexpression of AURKA can cause aneuploidy in urothelial cells, and the AURKA gene copy number is a promising biomarker for detection of bladder cancer.
To evaluate the utility of the holmium laser for partial nephrectomy in a porcine model.
Transperitoneal lower pole laparoscopic partial nephrectomy was performed in 5 farm pigs. All animals underwent a left-sided laparoscopic partial nephrectomy and were kept alive for 2 weeks (survival group). Subsequently, a right laparoscopic partial nephrectomy was performed (acute group), and the animals were sacrificed. A 1000-μm (n=6) or 550-μm (n=4) end-fire holmium laser fiber set at 0.2 joules and 60 pulses per second was used to transect the lower pole of the kidney 1 cm below the level of the hilum. The cut parenchymal surface was then sealed with fibrin glue in the survival animals. The operated on kidneys were inspected grossly and evaluated microscopically.
Laser transection was successfully completed in all cases, and hemostasis proved adequate without any adjunctive measures. No perioperative complications occurred. Estimated blood loss was less than 50 cc for each laparoscopic partial nephrectomy. The acute and survival pigs showed no statistically significant differences in specimen size or weight. Serum creatinine levels were normal in all survival animals. Extravasation was noted on retrograde pyelograms of 2 animals in the survival group.
The Holmium:YAG laser provides an efficacious modality for transecting the kidney in a porcine model. Clinical trials are necessary to determine its role in laparoscopic partial nephrectomy in humans.
Holmium laser; Partial nephrectomy; Laparoscopy; Kidney; Porcine model
Ovarian vein syndrome is a rare cause of ureteral obstruction. In this report, we describe an unusual presentation of the syndrome successfully treated with laparoscopic techniques.
The patient presented with a 12-month history of right flank pain and a right abdominal mass. The preoperative evaluation revealed renal malrotation, hydronephrosis, decreased renal function, and presumed ureteropelvic junction obstruction.
By using a transperitoneal laparoscopic approach, an enlarged ovarian vein was identified as the cause of the ureteral obstruction. The ovarian vein was divided with a laparoscopic stapler. The patient's postoperative course was unremarkable, and she was discharged from the hospital on the second postoperative day. At 3-months follow-up, the patient was completely asymptomatic without evidence of obstruction.
Ovarian vein syndrome remains a rare diagnosis of exclusion. A careful preoperative evaluation is required to exclude other causes of ureteral obstruction. By using a laparoscopic approach, the ureter and obstructing vessel were readily identified to effectively treat the patient. With the minimally invasive approach, postoperative recovery and patient quality of life were improved.
Laparoscopy; Ureteral obstruction; Ovarian vein syndrome
Background and Objectives:
To evaluate the experience with laparoscopic nephrectomy in a large county hospital and perform a cost comparison between uncomplicated open and laparoscopic nephrectomy.
Eleven consecutive patients who underwent an uncomplicated laparoscopic nephrectomy in a large county hospital were compared with 8 patients who underwent uncomplicated open nephrectomy during the same period. Patient charts and corresponding billing records were reviewed to determine overall hospitalization cost and individual cost components.
No perioperative complications occurred in either the laparoscopic or open group, and no statistically significant differences existed between groups with regard to patient demographics or operative parameters. The overall operating room costs favored the open nephrectomy group by $1070 (P=0.003). However, the overall cost of hospitalization, surgeon professional fees, duration of hospitalization, room and board costs, laboratory, and radiology costs, pharmacy costs, intravenous solution and infusion pump costs all significantly favored the laparoscopic patient group. The mean difference in overall hospital cost between laparoscopic and open nephrectomy was $1211 in favor of laparoscopy (P=0.037).
Our experience with laparoscopic nephrectomy in a large county hospital demonstrates a clear economic advantage in favor of the laparoscopic approach. Given limited funding for public hospitals and a clear patient benefit, laparoscopic nephrectomy should constitute first-line therapy when nephrectomy is indicated.
Laparoscopic nephrectomy; Cost comparison